Question

A motorcyclist drives from a to b with a uniform speed of 30 kilometre per hour and returns back with a speed of 20km/h find its average speed

Answer 1

Answer:

Let the distance = x km

Speed = distance/time

=x/time taken to go to job

In going : speed=distance / time

30=x/time

time=x/30

While returning: distance is same=x

new time=time'

speed = distance/time

20=x/time'

time'=x/20

Average speed: total distance/total time

: x+x/x/30+x/20

: 2x/5x × 60

: 24 km/h